Lawn mower

ABSTRACT

The present invention provides a lawn mower comprising a battery system, a walking system and a cutter system. The lawn mower further comprises: a fault detection module, configured to detect if at least one of the battery system, walking system and cutter system has a fault; a fault determination module, configured to judge the fault level of the detected fault; and a control module, to control the current-limiting or outage of the corresponding battery system, the slowdown or stop of the walking system, as well as the slowdown or stop of the cutter system according to the fault level; compared with the prior art, the invention not only makes the fault detection more intelligent, but also the lawn mower can adjust the working state in real time according to the fault level, thereby improving the working efficiency.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a US application which claims the priority of CNApplication Serial No. 201811415924.2, filed on Nov. 26, 2018, thedisclosures of which are hereby incorporated by reference in theirentirety.

TECHNICAL FIELD

The present invention relates to a lawn mower.

BACKGROUND ART

Lawn mower is a dedicated equipment for mechanically mowing the lawn.Because it is a dedicated equipment, so the lawn mower will have a sharpblade. The sharp blade is in a high-speed rotation state when working.Therefore, in order to ensure safety, the lawn mower must be checked ifthere is a failure in real time manner, in case the sharp blade is stillin high-speed rotation when a fault occurs, and this will cause a dangerwhich is difficult to predict.

At present, when the mower experiences a failure, it is displayedthrough the instrument panel, reminding the operator to shut down forfault diagnosis, and shutting down directly in serious cases, withoutautomatically detecting the fault and making corresponding actions, theintelligence of the lawn mower is poor.

In view of this, it is indeed necessary to make further improvements tothe existing lawn mower to solve the above problems.

SUMMARY OF INVENTION

The object of the present invention is to provide a novel lawn mowerwhich can detect faults and classify the detects faults into differentlevel automatically in order to make corresponding actions based on thefault level.

To achieve the above objectives, the invention provides a lawn mowercomprising a battery system, a walking system and a cutter system, andthe lawn mower further comprising: a fault detection module, configuredto detect if at least one of the battery system, walking system andcutter system has a fault respectively; a fault determination module,configured to judge the fault level of the detected fault; a controlmodule, configured to control the current-limiting or outage of thecorresponding battery system, the slowdown or stop of the walkingsystem, as well as the slowdown or stop of the cutter system accordingto the fault level.

In some embodiments, said lawn mower further comprises a maincontroller, and said fault determination module and said control moduleare disposed on said main controller, fault detection module comprises aplurality of fault detection module provided in the battery system, thewalking system and the cutter system respectively, to detect faultsthereof respectively.

In some embodiments, when said fault detection module detects that saidwalking system has a fault, said fault detection module sends a faultcode to the fault determination module through CAN communication todetermine a fault level, and said control module sends a control commandto the walking system through CAN communication according to the faultlevel to control said walking system to slow down or stop.

In some embodiments, when a minor fault occurs in the walking system,said control module sends a speed down command to said walking systemthrough CAN communication to slow down the walking speed; when a severefault occurs in the walking system, said control module sends a stopcommand to said cutter system through CAN communication, andsimultaneously sends a throttle supply shutdown signal to said walkingsystem, so that the lawn mower is in the mode: stop walking, and thecutter is not running.

In some embodiments, when said fault detection module detects that saidcutter system has a fault, said fault detection module sends a faultcode to the fault determination module through CAN communication todetermine a fault level, and said control module sends a control commandto the cutter system through CAN communication according to the faultlevel to control said cutter system to slow down or stop.

In some embodiments, when a minor fault occurs in the cutter system,said control module sends a speed down command to said cutter systemthrough CAN communication to slow down the revolving speed of thecutter; when a severe fault occurs in the cutter system, said controlmodule sends a stop command to said cutter system through CANcommunication, so that the lawn mower is in the mode: normal walking,and the cutter is not running.

In some embodiments, said battery system is connected to said maincontroller through CAN communication to realize real-time transmissionof a fault code and a control command, and said battery system has adischarge mode and a charging mode.

In some embodiments, when a minor fault occurs in said battery system inthe discharge mode, said control module sends a current limiting commandto said battery system, simultaneously sends a speed down command tosaid walking system, sends a stop command to the cutter system, to makethe lawn mower in the mode: low speed walking, and the cutter is notrunning; when said battery system experiences a severe fault in thedischarge mode, said control module sends a power-off command to thebattery system, and simultaneously sends a stop command to said cuttersystem, and sends a throttle supply shutdown signal to said walkingsystem, so that the mower is in the mode: stop walking, and the cutteris not running.

In some embodiments, when said battery system experiences a minor faultin the charging mode, said control module sends a current limitingcommand to the battery system, and controls a battery to continuecharging; when said battery system experiences a severe fault in thecharging mode, said control module sends a power-off command to saidbattery system, and cuts off the charging relay to stop a battery fromcharging.

In some embodiments, failures of said battery system in the dischargemode include the individual voltage is too low, the individual voltagedifference is too high, the discharge temperature is too low, thedischarge current is too high, the insulation resistance is too low, themaster-slave MCU communication failure, the master-slave MCU hardwarefailure, and the feedback current is too high; failures of the batterysystem in the charging mode include the individual voltage is too high,the individual voltage difference is too high, the charging temperatureis too high, the charging temperature is too low, the insulationresistance is too low, the master-slave MCU communication failure, andthe master-slave MCU hardware failure.

The beneficial effects of the present invention are: as the lawn mowerin the invention is provided with a fault detection module, a faultdetermination module and a control module, so that the lawn mower in theinvention can perform automatic detection through a fault detectionmodule, then perform a fault level determination through a faultdetermination module when the battery system, the walking system or thecutter system of the lawn mower have a fault, so that the control modulecan control the current-limiting or outage of the corresponding batterysystem, the slowdown or stop of the walking system, as well as theslowdown or stop of the cutter system; compared with the prior art, theinvention not only makes the fault detection more intelligent, but alsothe lawn mower can adjust the working state in real time according tothe fault level, thereby improving the working efficiency.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a control system diagram of the lawn mower of the presentinvention.

FIG. 2 is a control system diagram of the lawn mower in discharge mode.

FIG. 3 is a control system diagram of the lawn mower in low power mode.

FIG. 4 is a flow diagram of the lawn mower in charging mode.

DESCRIPTION OF EMBODIMENTS

In order to make the objects, technical solutions and advantages of thepresent invention more clearly, the present invention will be describedin detail below with reference to the drawings and specific embodiments.

The invention provides a lawn mower comprising a battery system, awalking system, a cutter system, and a control system for controllingthe walking system and the cutter system. The battery system isconfigured to provide power to a lawn mower; said walking system isconfigured to drive the lawn mower to perform self-propelling, and thewalking system comprises a walking wheel and a self-propelled motor fordriving the walking wheel to self-propelled; said cutter system includesa cutter and a cutter motor for driving the cutter to rotate. Of course,said lawn mower further comprises other structures, such as a switchsystem, a control lever, a casing, etc., and since these structures areprior art, they will not be described in detail herein.

The lawn mower further comprises a fault detection module, a faultdetermination module and a control module, and the fault detectionmodule, the fault determination module and the control module areelectrically connected by CAN communication. The fault detection moduleis configured to detect if at least one of the battery system, walkingsystem and cutter system has a fault respectively; the faultdetermination module is configured to judge the fault level of thedetected fault; and the control module is configured to control thecurrent-limiting or outage of the corresponding battery system, theslowdown or stop of the walking system, as well as the slowdown or stopof the cutter system according to the fault level.

It should be noted that, in this embodiment, the fault level is dividedinto a minor fault and a severe fault. Under a minor fault, the controlmodule controls the battery system to limit the current, the walkingsystem to reduce the speed by 20-80%, and the cutter system to reducethe speed by 20-80%. However, it does not affect the work of the entiremower; under severe faults, the control module controls the batterysystem to be powered off, the walking system to stop, the cutter systemto stop, and the entire mower to stop working. Of course, the faultlevel may also include a medium fault. In this case, the working stateof the lawn mower can be adjusted only by limiting the control commandissued by the control module; at the same time, the ratio of the speedreduction of the walking system and the cutter system can be arbitrarilyselected. There are no restrictions here.

Preferably, fault detection module comprises a plurality of faultdetection module provided in the battery system, the walking system andthe cutter system respectively, to detect faults thereof respectively;The fault determination module and the control module are provided inthe control system to adjust/control the working state of the batterysystem, the walking system, and the cutter system.

Referring to FIG. 1, the control system comprises a main controller, aslave controller and a cutter controller respectively connected to themain controller through CAN communication, and the fault determinationmodule and the control module are disposed on the main controller.Specifically, the slave controller corresponds to the walking system,and the slave controller is configured to collect the state of the firstself-propelled motor and the fault of the walking system in real time,and send the fault information to the control module in real time. Thecutter controller corresponds to the cutter system, and the cuttercontroller is configured to collect the state of the cutter motor andthe fault of the cutter system in real time, and send the faultinformation to the control module in real time. As the control core ofthe mower, the main controller is responsible for real-time acquisitionof the state of the second self-propelled motor and the failure of thewalking system, and on the other hand, collecting information of thebattery system, the slave controller and the cutter controller, and themain controller will send the control command and status information tothe cutter controller, the slave controller and the instrument afterprocessing, to realize the running or stopping of the walking system andthe cutter system, and also realize the real-time display of the wholemachine state, and then realize the systematic protection of the wholemachine.

When the fault detection module detects that the walking system has afault, the fault detection module sends a fault code to the faultdetermination module through CAN communication to determine a faultlevel, and said control module sends a control command to the walkingsystem through CAN communication according to the fault level to controlthe walking system to slow down or stop. Specifically, when a minorfault occurs in the walking system, the control module sends a speeddown command to the walking system through CAN communication, thewalking system reduces the walking speed by 20-80% according to thespeed down command; when a severe fault occurs in the walking system,the control module sends a stop command to the cutter controller throughCAN communication, the main controller and the slave controller closethe throttle supply signal respectively, so that the walking speed ofthe mower is reduced to 0, and the electromagnetic brake 1 andelectromagnetic brake 2 are released, at this time, the mower is in themode:stop walking, and the cutter is not running.

The faults of the walking system include the failure of the maincontroller and/or the slave controller and the fault of theself-propelled motor. The faults of the self-propelled motor mainlyinclude the over temperature of the motor, the stall of the motor, theabnormality of the encoder of the motor, and the open circuit of themotor; The main controller fault is the same as the slave controllerfault, which mainly includes the controller's own fault and theuser-defined fault. The controller's own fault mainly includes theworking voltage abnormality, the working temperature abnormality, themotor overcurrent, the precharge abnormality, the input abnormality, theoutput abnormality and the communication abnormality; user-definedfaults are mainly the additional protection functions based on the needsof the whole machine.

When the fault detection module detects that the cutter system has afault, the fault detection module sends a fault code to the faultdetermination module through CAN communication to determine a faultlevel, and said control module sends a control command to the cuttersystem through CAN communication according to the fault level to controlthe cutter system to slow down or stop. Specifically, when a minor faultoccurs in the cutter system, the control module sends a speed downcommand to the cutter system through CAN communication, the cuttersystem reduces revolving speed of the cutter by 20-80% according to thespeed down command; when a severe fault occurs in the cutter system, thecontrol module sends a stop command to the cutter controller through CANcommunication, so that the lawn mower is in the mode: the walking systemworks normally and the cutter system does not work. At the same time,the meter displays a fault message to alert the user to troubleshooting.

The faults of the cutter system include the cutter motor fault, thecutter fault and the cutter controller fault. The cutter motor faultmainly includes the motor over temperature, the motor stall, the motorencoder abnormality, the circuit phase open circuit, etc.; the cuttercontroller fault mainly includes working voltage abnormality, workingtemperature abnormality, motor overcurrent, MOS tube abnormality,precharge abnormality, CAN communication abnormality and so on.

Since there are a plurality of cutters in the lawn mower, the cuttercontroller is also provided in plurality so that one cutter controllercorresponds to one cutter. When any cutter fails (such as overtemperature), the cutter controller can automatically detect and sendthe fault code to the fault determination module through CANcommunication, after which the control module sends a stop command toall cutter controllers, controlling all cutters to stop working, toavoid the situation that the cutters does not work at the same time. Atthis time, the lawn mower is in the mode: the walking system worksnormally and the cutter system does not work.

In addition, under normal circumstances, the cutter controller willmonitor the cutter speed, current, voltage and other information in realtime, and send the information to the main controller in real time. Ifthe main controller doesn't receive the message sent from the cuttercontroller in 2 s, the main controller can determine that the cuttercontroller is abnormal in communication, and the control module controlsthe lawn mower to enter the mode: the walking system works normally andthe cutter system does not work.

The battery system is connected to said main controller through CANcommunication to realize real-time transmission of a fault code and acontrol command. Because the battery system is the link between thebattery and the user, the main purpose is to improve the utilization ofthe battery and prevent the battery from being overcharged andover-discharged. Therefore, the battery system has a discharge mode anda charging mode. Because the battery system has a fault self-detectionfunction, so after the battery system receives the power-onsignal/charge signal, the fault detection and level determination areautomatically performed, and then the fault code is sent to the controlmodule through the CAN communication, and the control module issues acorresponding control command.

Please refer to FIG. 2, in discharge mode, when a minor fault occurs inthe battery system, the control module sends a current limiting commandto the battery system, simultaneously sends a speed down command to thewalking system, sends a stop command to the cutter system, to make thelawn mower in the mode: low speed walking, and the cutter is notrunning; when a severe fault occurs in the battery system, controlmodule sends a power-off command to the battery system, andsimultaneously sends a stop command to the cutter system, and sends athrottle supply shutdown signal to the walking system, so that the moweris in the mode: stopwalking, and the cutter is not running.

Specifically, when a minor fault occurs, the battery system sends aminor fault to the control module of the main controller through CANcommunication. After receiving the fault, the control module sends thefault to the slave controller, and then the slave controller controlsthe corresponding first self-propelled motor and the main controllercontrols the corresponding second self-propelled motor, and controls therunning speeds of the two self-propelled motors to the low speed mode,and the control module sends a stop command to the cutter controller tomake the mower in the mode: low-speed walking, and the cutter is notrunning, thereby reducing the discharge current and preventing otherabnormalities from been raised due to the a large discharge current whenthe battery has a failure.

When a severe fault occurs, the battery system sends the severe fault tothe control module of the main controller through CAN communication.After receiving the fault, the control module sends the fault to theslave controller. At this time, the master controller and the slavecontroller respectively close the throttle supply signal to reduce thewalking speed of the mower to 0, release the electromagnetic brake 1 andthe electromagnetic brake 2, and the control module sends a stop commandto the cutter controller, so that the mower is in the mode: stopwalking, and the cutter is not running And after 15 s, the relay insidethe battery is cut off, so that the battery stops outputting.

Failures of said battery system in the discharge mode mainly include theindividual voltage is too low, the individual voltage difference is toohigh, the discharge temperature is too low, the discharge current is toohigh, the insulation resistance is too low, the master-slave MCUcommunication failure, the master-slave MCU hardware failure, and thefeedback current over high and other major failures; of course, itincludes but not limiting to the above failures.

Please refer to FIG. 3, in the discharge mode, the battery system alsohas low-power protection function. Low-power protection mainly meansthat when the battery is in low power status, the mower reduces theoperation power, and meter displays the battery power and flashes toremind the user to charge in time to prevent the mower from unable towalk due to excessive use, and prevent the battery fromover-discharging, which affects the service life.

Low power of the battery is mainly divided into two grades, the highgrade is 5% rated capacity of the battery, and the low grade is 2% ofthe rated capacity of the battery. When the remaining capacity of thebattery is ≤5%, the control module of the main controller sends a lowspeed command to the cutter controller through CAN communication to slowdown the cutter, and simultaneously sends a low speed command to theslave controller to reduce the walking speed. At the moment, the meteris flashing and the mower is in low power mode. When the remainingcapacity of the battery is ≤2%, the control module of the maincontroller sends a low speed command to the slave controller through CANcommunication to make the walking system remain in low speed status, andsimultaneously sends a stop running command to the cutter controller tomake the cutter stall. Thereby, the power consumption of the mower isfurther reduced, and the meter power is flashing, and the mower is in acharging preparation state.

Please refer to FIG. 4, in the charging mode, when said battery systemexperiences a minor fault, the control module sends a current limitingcommand to the battery system, and controls a battery to continuecharging; when the battery system experiences a severe fault, thecontrol module sends a power-off command to the battery system, and cutsoff the charging relay to stop a battery from charging.

Failures of said battery system in the charging mode mainly include theindividual voltage is too high, the individual voltage difference is toohigh, the charging temperature is too high, the charging temperature istoo low, the insulation resistance is too low, the master-slave MCUcommunication failure, the master-slave MCU hardware failure and othermajor failures.

In the charging mode, the battery system also has a heating protectionfunction at low temperatures. The heating protection at low temperatureis mainly to improve the temperature inside the battery by the heatingmodule to reduce damage to the battery core due to low temperaturecharging, thereby prolonging the service life of the battery core. Whenthe battery is ready to be charged, if the battery system detects thatthe lowest temperature in the battery box is higher than 2° C., thebattery system sends a charging command to the charger, the chargerstarts to work, and the battery enters the charging mode; If the batterysystem detects that the lowest temperature in the battery box is lowerthan 2° C., the battery system sends a heating command to the charger,and at the same time closes the heating relay, and the battery entersthe heating mode; when the temperature inside the battery box reaches 5°C., the battery system sends a charging command to the charger, and thebattery enters a mode of charging while heating; when the temperatureinside the battery box reaches 10° C., the charger enters the chargingmode, the battery system disconnects the heating relay, closes thenegative relay and the charging relay, and the battery enters thecharging mode.

It should be noted that when the battery is ready to be charged, if itis detected that the lowest temperature in the battery box is higherthan 2° C., it means that the external temperature at this time issuitable, and ‘the charging mode can be directly entered. If it isdetected that the lowest temperature in the battery box is lower than 2°C., it means that the external temperature at this time is very low,such as minus ten degrees, so the charger needs to be heated first, andthe charger does not enter the charging mode at this time; when thetemperature in the battery box reaches 2° C. (or 5° C.), if the heatingis stopped at this time, the temperature in the battery box willdirectly drop below 2° C., thereby damaging the life of the battery, soit is necessary to continue heating the charger to ensure that thetemperature does not drop, at this time the charger is charged whileheating; when the temperature in the battery box reaches 10° C., itmeans that the temperature of the battery at this time is balanced withthe external temperature. It is not necessary to continue heating, andthe battery directly enters the charging mode.

In the present invention, taking the battery system as an example, forthe level determination of minor faults and severe faults, please referto the following table. When the battery status reaches the alarmthreshold of each level and continues to exceed the “alarm delay”, thebattery system will report the corresponding level of alarm; whenreporting the first level alarm (corresponding to a severe fault) andcontinues to exceed the “cutoff delay”, the battery system will turn offthe corresponding relay; when the parameter is configured as “/”, thecorresponding alarm and cut-off functions are disabled.

Serial Set Restore Alarm Cutout Fault Number Project Value ValueRequirements Delay Delay Level 1 Upper Limit 52 47 Set the upper 2 S /Minor of Discharge limit of Fault Temperature temperature 1 (° C.)threshold 1, alarm, the maximum discharge power is reduced to 50% 2Upper Limit 56 / Set the upper 2 S 15 S Severe of Discharge limit ofFault Temperature temperature 2 (° C.) threshold 2, alarm, the maximumdischarge power is reduced to 0%, cut off the high voltage after 15 sdelay 3 Upper Limit 50 45 Set the upper 2 S / Minor of Charging limit ofFault Temperature temperature 1 (° C.) threshold 1, alarm 4 Upper Limit56 / Set the upper 2 S 15 S Severe of Charging limit of FaultTemperature temperature 2 (° C.) threshold 2, alarm, the maximumfeedback power is reduced to 0% 5 Lower Limit −15 −10 Set the lower 2 S/ Minor of Discharge limit of Fault Temperature temperature 1 (° C.)threshold 1, alarm, the maximum discharge power is reduced to 50% 6Lower Limit −20 / Set the lower 2 S 15 S Severe of Discharge limit ofFault Temperature temperature 2 (° C.) threshold 2, alarm, the maximumdischarge power is reduced to 0%, cut off the high voltage after 15 sdelay 7 Lower Limit 5 10 Set the lower 5 S / Minor of Charging limit ofFault Temperature temperature 1 (° C.) threshold 1, alarm 8 Lower Limit2 / Set the lower 5 S  1 S Severe of Charging limit of Fault Temperaturetemperature 2 (° C.) threshold 2, alarm, the maximum charging power isreduced to 0%, cut off the charging loop after 1 s delay 9 Individual0.5 0.3 The maximum 2 S / Minor voltage voltage Fault difference isimbalance too high 1 value allowed (V) between all cabinets 1, alarm,the maximum discharge power is reduced to 50%. 10 Individual 0.7 / Themaximum 2 S 15 S Severe Voltage voltage Fault difference is imbalancetoo high 2 value allowed (V) between all cabinets 2, alarm, the maximumdischarge power is reduced to 0%, cut off the high voltage after 15 sdelay 11 Battery 12 7 The maximum 2 S / Minor temperature temperatureFault difference is imbalance too large 1 value allowed (° C.) betweenall cabinets 1, alarm, the maximum discharge power is reduced to 50%. 12Battery 15 / Alarm, the 2 S 15 S Severe temperature maximum Faultdifference is discharge too large 2 power is (° C.) reduced to 0%, cutoff the high voltage after 15 s delay 13 Individual 3.65 3.6 The maximum2 S / Minor voltage is individual Fault too high 1 voltage (V) allowedin the battery 1, alarm, the maximum discharge power is reduced to 50%14 Individual 3.7 / The maximum 2 S  5 S Severe voltage is individualFault too high 2 voltage (V) allowed in the battery 2, alarm, themaximum discharge power is reduced to 0%, cut off the high voltage after5 s delay 15 Individual 2.8 / The minimum 2 S 15 S Severe voltage isindividual Fault too low 2 voltage (V) allowed in the battery 2, alarm,the maximum discharge power is reduced to 0%, cut off the high voltageafter 15 s delay 16 Charging 35 30 The maximum 2 S / Minor current istoo current allowed Fault high 1 (A) when charging 1, alarm, the maximumcharging power is reduced to 50%. 17 Charging 40 / The maximum 2 S 15 SSevere current is too current allowed Fault high 2 (A) when charging 2,alarm, the maximum charging power is reduced to 0%, cut off the highvoltage after 15 s delay 18 Discharge 250 200 The maximum 2 S / Minorcurrent is too current allowed Fault high 1 (A) when discharging 1,alarm, the maximum discharging power and feedback power are reduced to50%. 19 Discharge 270 / The maximum 2 S  3 S Severe current is toocurrent allowed Fault high 2 (A) when discharging 2, alarm, the maximumdischarging power is reduced to 0%, cut off the high voltage after 3 sdelay 20 Minor 40 100 Alarm, the 60 S  / Minor insulation maximum Faultfaults (KΩ) discharging power and feedback power are reduced to 80%. 21Severe 10 / Alarm, the 60 S  15 S Severe insulation maximum Fault fault(KΩ) discharge power and feedback power is reduced to 0%, cut off thehigh voltage after 15 s delay, if the power is being self- tested, highvoltage is not allowed. 22 Battery 5 s / Alarm, the 5 S 30 S Severesystem maximum Fault internal discharge master-slave power andcommunication feedback fault power is reduced to 0%, cut off the highvoltage after 30 s delay 23 Battery 2 s / Alarm, the 2 S 15 S Severesystem self-test maximum Fault hardware discharge fault power andfeedback power is reduced to 0%, cut off the high voltage after 15 sdelay 24 Feedback 80 50 The maximum 2 S / Minor current is too feedbackFault high 1 (A) current allowed when discharging 1, alarm, the maximumdischarging power and feedback power are reduced to 50%. 25 Feedback 100/ The maximum 2 S 15 S Severe current is too feedback Fault high 2 (A)current allowed when discharging 2, alarm, the maximum discharging poweris reduced to 0%, cut off the high voltage after 15 s delay

Of course, for the determination rules of the fault level of the walkingsystem and the cutter system, please set by referring to the abovetable, which is not limited herein.

In conclusion, the beneficial effects of the present invention are: asthe lawn mower in the invention is provided with a fault detectionmodule, a fault determination module and a control module, so that thelawn mower in the invention can perform automatic detection through afault detection module, then perform a fault level determination througha fault determination module when the battery system, the walking systemor the cutter system of the lawn mower have a fault, so that the controlmodule can control the current-limiting or outage of the correspondingbattery system, the slowdown or stop of the walking system, as well asthe slowdown or stop of the cutter system; compared with the prior art,the invention not only makes the fault detection more intelligent, butalso the lawn mower can adjust the working state in real time accordingto the fault level, thereby improving the working efficiency.

The above embodiments are only used to illustrate the technicalsolutions of the present invention, not for limitation. Although thepresent invention is described in detail with reference to the preferredembodiments, ordinary technicians in the field should understand thatthe technical solutions of the present invention may be modified orsubstituted without departing from the spirit and scope of the technicalsolutions of the present invention.

We claim:
 1. A lawn mower, comprising a battery system, a walking systemand a cutter system, wherein further comprising: a fault detectionmodule, configured to detect if at least one of the battery system,walking system and cutter system has a fault respectively; a faultdetermination module, configured to judge the fault level of thedetected fault; a control module, configured to control thecurrent-limiting or outage of the corresponding battery system, theslowdown or stop of the walking system, as well as the slowdown or stopof the cutter system according to the fault level.
 2. The lawn moweraccording to claim 1, wherein said lawn mower further comprises a maincontroller, and said fault detection module comprises a plurality offault detection module provided in the battery system, the walkingsystem and the cutter system respectively, to detect faults thereofrespectively.
 3. The lawn mower according to claim 2, when said faultdetection module detects that said walking system has a fault, saidfault detection module sends a fault code to the fault determinationmodule through CAN communication to determine a fault level, and saidcontrol module sends a control command to the walking system through CANcommunication according to the fault level to control said walkingsystem to slow down or stop.
 4. The lawn mower according to claim 3,when a minor fault occurs in the walking system, said control modulesends a speed down command to said walking system through CANcommunication to slow down the walking speed; when a severe fault occursin the walking system, said control module sends a stop command to saidcutter system through CAN communication, and simultaneously sends athrottle supply shutdown signal to said walking system, so that the lawnmower is in the mode: stop walking, and the cutter is not running. 5.The lawn mower according to claim 2, when said fault detection moduledetects that said cutter system has a fault, said fault detection modulesends a fault code to the fault determination module through CANcommunication to determine a fault level, and said control module sendsa control command to the cutter system through CAN communicationaccording to the fault level to control said cutter system to slow downor stop.
 6. The lawn mower according to claim 5, when a minor faultoccurs in the cutter system, said control module sends a speed downcommand to said cutter system through CAN communication to slow down therevolving speed of the cutter; when a severe fault occurs in the cuttersystem has, said control module sends a stop command to said cuttersystem through CAN communication, so that the lawn mower is in the mode:normal walking, and the cutter is not running.
 7. The lawn moweraccording to claim 2, wherein said battery system is connected to saidmain controller through CAN communication to realize real-timetransmission of a fault code and a control command, and said batterysystem has a discharge mode and a charging mode.
 8. The lawn moweraccording to claim 7, when a minor fault occurs in said battery systemin the discharge mode, said control module sends a current limitingcommand to said battery system, simultaneously sends a speed downcommand to said walking system, sends a stop command to the cuttersystem, to make the lawn mower in the mode: low speed walking, and thecutter is not running; when said battery system experiences a severefault in the discharge mode, said control module sends a power-offcommand to the battery system, and simultaneously sends a stop commandto said cutter system, and sends a throttle supply shutdown signal tosaid walking system, so that the mower is in the mode: stop walking, andthe cutter is not running.
 9. The lawn mower according to claim 7, whensaid battery system experiences a minor fault in the charging mode, saidcontrol module sends a current limiting command to the battery system,and controls a battery to continue charging; when said battery systemexperiences a severe fault in the charging mode, said control modulesends a power-off command to said battery system, and cuts off thecharging relay to stop a battery from charging.
 10. The lawn moweraccording to claim 7, wherein failures of said battery system in thedischarge mode include the individual voltage is too low, the individualvoltage difference is too high, the discharge temperature is too low,the discharge current is too high, the insulation resistance is too low,the master-slave MCU communication failure, the master-slave MCUhardware failure, and the feedback current is too high; failures of thebattery system in the charging mode include the individual voltage istoo high, the individual voltage difference is too high, the chargingtemperature is too high, the charging temperature is too low, theinsulation resistance is too low, the master-slave MCU communicationfailure, and the master-slave MCU hardware failure.